Turbomax 282E Hot water

[CES]

Had a job during the week, customer had only lukewarm water at taps and shower, had a quick look and diverter valve ordered up as CH pipes were hot when HW was being called for. Changed DV and tested, all appeared to be ok.
Now woke up to email saying that they tried running a bath last night and it wasnt getting hot, but taps in kitchen and the basin were hot and the shower was fine. Now I told them to slow the rate down when filling a bath but its got me thinking if Ive missed anything obvious? Its an old boiler (well 10yrs anyway) but Ive been told that it was working ok previously.
I would have thought that if you have HW everywhere else then it can only be the rate at which they are filling the bath. I hate it when I begin to doubt myself!
Anyone got any thoughts?

 

[aggis]

Sounds like flow rate, dhw t/stat turned up? If you have to go back check working pressure aswell as flow rate.

 

[CES]

Just been back to it for a proper look. The bloody thing was undergassed. How they had hot water at all is lucky! Going back to upgrade the pipe next week.

 

[SimonJohns]

Just been back to it for a proper look. The bloody thing was undergassed. How they had hot water at all is lucky! Going back to upgrade the pipe next week.

Think you may be barking up the wrong tree. Its been installed for 10+ years and. It had a fault with poor gas supply pipe. Wether or not the gas pipe was undersized

My bets would be.
Flow rate
Scaled plates
Modulation coil on GV
Obstruction in water ways in boiler( debris in plates/debris in pump)

 

[CES]

Thanks for the replies, inlet pressure to gas valve was 6.5mbar, should be 18 min.gas rate was 2.1m3/hr, should be 3.3. I can get hot water at reasonable temp if flow is reduced but this should give 11ltrs/min. We've got pretty soft water up here so scales not an issue. I'll have a look at dhw exchanger and coil next week.

 

[SimonJohns]

6.5. Did you check working at meter. I would find it weird to just change now after so many years

 

[CES]

Yes it was 20mbar at meter. Never came across this before either, hence I'm doubting myself a bit

 

[SimonJohns]

Seems such a strange fault after so many years if correct operation

I understand that it is a fault. But have you checked other things

I wouldn't dream of checking a inlet pressure of it has been working for so long. Unless it had a faulty reg

Has the valve been turned off half way. Has any new appliances been fitted. Is there a massive leak.

Personally. I would look for another fault. BUT. Every job is different and your the one that has seen the job

 

[CES]

The thing is correct max burner pressure is about 10mb, so during the summer it was probably reaching that when gas demand was lower than now. The original fault was def the DV as they are now getting hot water albeit not at a great flow rate. Im getting 6.5mb in and 6.5mb out of the gas valve so Im assuming the mod coil is ok.

 

[stevetheplumber]

never assume something worked right because its been in years i found a gas supply pipe full of hardened boss white on a boiler which would barely make min gas rate been fitted 15 years
removed blockage and got it all working right customer didnt stop complaining after boiler was noisey and kept going of
reason it was going of was it had never got hot enough before .situation was finally resolved when she called corgi in to check it and they told her it was right but she wasnt happy she prefered the boiler on 24/ 7 as it warmed the kitchen

 

[diamondgas]

CES, What was the end result after upgrading the pipework?

I had a job month or so back that had me scratching the old head regards inlet pressure dropping to 10mbar! When i took the gas valve out the filter was full of 'silver flakes'!!! Crud from the mains had blocked the valves believe it or not!!

 

[CES]

Ive not been back to upgrade it yet Diamondgas. Been waiting on a phonecall to get the go ahead. Ill let you know as soon as I know whats happening with it.